How to Solve Replication lag? quick solution

This topic is not for all situations but in my situation it helps. The problem is with Slave is lagging behind master in very large numbers and the relay logs are continously growing.

Slave is using: Relay_Log_File: mysql-relay-bin.000031.
But in folder where relay log resides, was created up to: mysql-relay-bin.000135 And it is continously growing.
So what i decide to do, again step-by-step i edited my.cnf file as follows: